Just thought I would share an interesting observation from this last week.

Usually, I am not a machine user (excluding treadmill for sprinting on) and prefer body weight workouts. However, I was a tad bit mentally fatigued and wanted to do about an hour of elliptical and not have to think too hard. A good focused workout usually requires the mind to be focused and a good response from the CNS. My philosophy that day was I would rather do something then nothing.

So I put in my age and weight and do a hill program with some tough resistance. I did my hour and it says 1200 calories. I worked it pretty well and had puddles of sweat to prove it. I also wore my fancy heart rate monitor, including the chest strap making sure everything was calibrated before starting.

After reading 1200, I look down at my watch and it says 640 calories. Man, that is a really large error margin. And it is a commercial precor model, albeit a pretty old model (90s I think). I trust my polar heart rate monitor much more than the machine since I have started using it, but was still a little put off by the discrepancy. Maybe I am in much better shape in terms of heart rate and max vox2 than the machine thought I was with respect to the programming in it given age and height; remember, it does not have a hr sensor.

No wonder I had trouble losing weight in the past when using this elliptical machine at home with a not so clean diet (many years ago, before VSG). I had always thought I was burning twice as many calories as I really did. I do not have a problem with diet today (thanks to VSG post op), but I did back then and always tried to burn a lot of calories to offset the calories from my junky diet.

Maybe this story and information will help someone.

Thanks for this post! I am mystified by the calorie indicators on most of my tools. Today, for example, I did 20 minutes of moderate elliptical ("jog") and 45 minutes of recumbent elliptical, again, moderate. The machines told me based on my weight and age that I burned 451 calories for that 65 minutes. My Fitbit said I burned 1,170 calories (please note that it only picked up "38 active minutes"). Add onto that my Spark People fitness minutes - they say I burned 900. So which is it? This is just too crazy for me - I just assume I've burned enough to eat my 210 calorie Atkins pretzel bar, which I count as a "treat" each day.

I would say that the machine that has the best hr sensor wins. Those without heart rate sensors are only as good as the standard calorie calculator that is configurable with age and weight. Not accurate at all for the individual, but acceptable for the average. We are not average people!

Edited August 10, 201412 yr by Fiddleman

This is why I try not to eat my calories back. Then there's MyFitnessPal that grossly overestimates calories burned. So many people use that app and just trust.